Previously, many types of systems have been used to provide an effective means for accessing the rear wheel valve stem in a truck dual-wheel application or for providing a system that eliminates the need for extended valve stems.
A search of the prior art did not disclose any patents that possess the novelty of the instant invention; however the following U.S. patents are considered related:
Moore in U.S. Pat. No. 4,398,574 teaches a method of inflating the inner tire of dual pneumatic wheels using a valve extender. The valve extender is easily attached or detached, and also incorporates a coupling on one end which grips the wheel valve stem, and a connector on the other end for engaging the air supply hose.
U.S. Pat. No. 5,244,027 issued to Freigang is for a tire pressure control system for wheels of a motor vehicle. The system utilizes a compressed air control system and a vacuum negative pressure system with a control system for valves that vent and pressurize tires.
Beverly et al. in U.S. Pat. No. 5,253,687 also discloses a tire pressure control system for wheels of a vehicle. The system similarly utilizes a compressed air control system and a vacuum negative pressure system with a control system for valves that vent and pressurize tires.
Beverly et al. in U.S. Pat. No. 5,273,064 is a divisional patent for the above application of Beverly et al.
U.S. Pat. No. 5,429,167 issued to Jensen is for a central tire inflation system that is utilized basically for tractor trailer rigs. The system requires no modification to wheel hubs or axle tubes, with communication provided between an air reservoir through the axle hub and a spindle sleeve. A chamber includes a spindle hum, a hub cover, a rotary seal and a spindle sleeve attached to a nut. A control system includes a plurality of multi-port two-way pneumatic valves.
For background purposes and as indicative of the art to which the invention is related reference may be made to the remaining cited patent issued to Ford in U.S. Pat. No. 4,275,622.